/Engine/Plugins/Editor/UVEditor/Source/UVEditorTools/Public/ContextObjects/UVToolContextObjects.h
Since tool-independent changes usually operate on UV editor mesh input object, it is probably preferable to use EmitToolIndependentUnwrapCanonicalChange, which will set up a proper transaction for you.
virtual void EmitToolIndependentChange ( [UObject](API\Runtime\CoreUObject\UObject\UObject) * TargetObject, [TUniquePtr](API\Runtime\Core\Templates\TUniquePtr)< [FToolCommandChange](API\Runtime\InteractiveToolsFramework\FToolCommandChange) > Change, const [FText](API\Runtime\Core\Internationalization\FText) & Description )